March 22, 2004 The Baltimore Sun by Dennis O'Brien

Green onions from Mexico killed three patrons of a Pennsylvania restaurant and sickened more than 600 in the fall. Mad cow test standards were tightened last week, months after a Washington state Holstein was infected with the disease, traced to a Canadian herd.

A strain of avian flu discovered this month in Maryland - while no threat to humans - endangers the state's multimillion-dollar poultry industry. A deadlier strain has killed 23 people in Asia.

"I think what we're seeing is an unprecedented vulnerability of the safety of our food supply," said Dr. Robert Lawrence, a professor of preventive medicine at the Johns Hopkins University's Bloomberg School of Public Health.

The potential threat to our food increases as the world's population grows, travels more, harvests more of the world's forests and relies increasingly on crops supplied by industrial-size farms, experts say.

"By now, you should be relatively scared," Andrew P. Dobson, a Princeton University biologist, told scientists last week at the American Institute of Biological Sciences' annual conference in Washington.

Dobson noted that the epidemic of foot-and-mouth disease that infected British cattle in 2001 - effectively shutting down that nation's beef industry - started when one farmer fed leftover airline food to his cattle. The disease spread because the British government was slow to react, he said.

"It's a scary example for agriculture," Dobson said.

Experts say the threat is a direct result of our own appetites. "It's very much related to what the American consumer is looking for, the desire for seasonal fruit and vegetables year-round," said Dr. David W.K. Acheson, director of food safety and security for the Food and Drug Administration.

In an attempt to monitor the flood of imports, the FDA has hired 600 inspectors and plans to require 420,000 food importers to register and notify the agency before shipping food into the United States. New regulations

Under the new regulations, importers must give two hours' notice for goods moved by truck, four hours' notice for rail shipments and eight hours for ships coming into ports.

The notification requirements, which became effective in December, are intended to make it easier for FDA inspectors to identify incoming foodstuffs that might be suspicious. FDA's proposed budget calls for conducting 97,000 import inspections next year, a 60 percent increase over the current year.

But food safety advocates say the FDA and other government agencies are too understaffed to adequately inspect the 25,000 shipments of imported food that arrive each day.

Those imports have increased sharply since the North American Free Trade Agreement widened trade with Mexico and Canada - from $26 billion in 1994 to $46 billion last year. The value of imported vegetables has more than doubled since 1994, to a record $6.2 billion in 2003, according to federal agriculture reports.

"You have more food being imported across our borders, and our ability to inspect and enforce what's on the books is being taxed tremendously. I don't think we could even create a surveillance system to detect all of the potential problems," said Joseph Mendelson, legal director of the Center for Food Safety, a nonprofit advocacy group focused on the health and environmental effects of food production.

The FDA's Acheson said there is no way to guarantee an end to mad cow, avian flu, hepatitis A or any other agriculture-based pathogen. But he said the nation's food supply is safe and the upgraded inspection system should address concerns about threats from imports.

"Food-borne diseases are nothing new. It's not like we're having rampant outbreaks of things we've never seen before," he said. "I can't say we'll never have another incident. But we're doing everything we can to prevent them from happening."

The Centers for Disease Control and Prevention estimate that 25 percent of Americans are sickened by food each year. Although cases of mad cow disease and avian flu grab headlines, produce still poses the biggest health threat when it comes to food-related illnesses.

A survey by the Center for Science in the Public Interest, another nonprofit watchdog group, found that contaminated produce was responsible for more sickness than any other food source in 2002.

Reports to the CDC between 1990 and 2002 indicate there were 2,472 outbreaks of produce-borne illness, accounting for 18,084 cases. Multi-ingredient foods, such as pizza, ranked second, causing 330 outbreaks and 11,500 illnesses.

Exactly how many of those cases were caused by imported food remains unclear.

But experts say many food-borne illnesses are the result of improper cooking. Ground beef has been a cause of food-borne disease for 20 years, with E. coli bacteria killing an average of about 60 people in the United States annually. Contaminated produce

Green onions imported from Mexico to a Pennsylvania Chi-Chi's restaurant were linked to an outbreak of hepatitis A last fall that killed three people and sickened more than 600. There were smaller outbreaks in other states.

Experts say that much of the produce these days comes from Mexico and South America, where there are fewer inspections and more unsanitary conditions. Salmonella and E. coli are frequently linked to crop contamination caused by dirty irrigation water and untreated manure applied to fields.

Even modern farming practices here and abroad aren't helping, Lawrence said. Crowded chicken houses and large-scale cattle operations - a trend of the past 30 years - are models of efficiency. But packing cattle or chickens into confined quarters helps disease spread quickly.

"It just creates a breeding ground for infections and unhealthy conditions," Lawrence said. Mad cow

He said the threat from mad cow disease, or bovine spongiform encephalopathy (BSE), emerged in the 1970s when farmers expanded into huge, industrial cattle operations and began feeding herds ground up pieces of cows and other animals.

Mad cow is believed to be caused by cattle feed tainted by animals, which develop holes in their brain tissue when infected. Humans can contract a related illness, variant Creutzfeldt-Jakob disease, by eating contaminated beef. There is no drug to stop it from spreading; the only way to ensure public safety is to destroy the animals at risk.

More than 140 human deaths from mad cow disease were recorded in Britain and 10 elsewhere, but none in the United States.

Food safety advocates sharply criticized the U.S. government's initial response to the mad cow discovery in Washington state: a review of cattle feed requirements and a plan to test 20,000 of the 35 million cows slaughtered each year.

"They need to dramatically increase the number of cows tested," said Michael Hansen, a biologist and research associate for Consumers Union, which publishes Consumer Reports.

In the aftermath of the criticism, the U.S. Department of Agriculture announced plans last week to begin testing as many of the nation's 446,000 high-risk cattle as possible. High-risk cattle include those that cannot walk or stand. The FDA also is tightening cattle feed requirements. Avian flu

Researchers also are trying to determine how avian flu arrived in Maryland, threatening a poultry industry that generated $440 million in chicken and feed grain sales in 2002.

The flu, a virus spread by chickens' saliva and waste, was detected on the Eastern Shore this month, the first time that a commercial flock in Maryland was infected. The strain, known as H7, is not as lethal as the H5 form that has killed an estimated 23 people in Vietnam and Thailand.

But it has meant the destruction of 360,000 chickens, prompted dozens of countries to ban Maryland poultry and threatens the future of the industry.

Unlike some other pathogens, the corkscrew-shaped flu virus might have originated with ducks or geese that migrate along the East Coast.

The wild birds are captured and brought into contact with chickens sold at live poultry markets in urban areas. The infection could be arriving at poultry farms either in birds purchased at the markets or in the litter or saliva in the trucks that hauled them, experts say.

"The live-bird market is what's given us the problem with influenza," said David Wolfgang, director of field investigations for the department of veterinary science at Pennsylvania State University.

Although the flu strain in Maryland poses no risk to humans, Wolfgang and others warn that the virus can mutate as it passes from one animal to another, subtly changing the groupings of its molecular structure. The ability to mutate could create a strain that one day infects humans, he said.

"Every time it goes through an animal, there will be some shifts," Wolfgang said.